Tool for removing ridges from cylinder walls



June 30, 1936. O D 2,046,241

TOOL FOR REMOVING'RIDGES FROM CYLINDER WALLS Filed Jan. 8 1955 Emma-19,35 750 Patented June 30, 1936 UNITED, STATES LATENT oFFrc-E Tool. :FoR- REMOVING muons FROM CYLINDER WALIJS w 7 Lawrence 0. Beard, Lancaster, Application January 8, 1-935," Serial N0. 921

1 Claim.

This invention is an improvement of my tool for removing ridges from the walls of cylinders disclosed in my co-pending application Serial No. 727,827, filed May 26, 1934.

The principal object of the present invention is to provide a means pivotally mounted on the cutter blades for retaining the cutting tool in cutting position within the cylinder.

Another object is to provide supporting members for a cutting tool which can be readily removed to regrind the cutting blades.

Other and more specific objects and advantages Will be apparent as the specification is considered in connection with the accompanying drawing, in which:

Figure 1 is a plan View of the improved tool in operative position on a cylinder block;

Figure 2 is a section of Figure 1; and

Figure 3 is a perspective view of a cutter blade and supporting arm.

Referring more particularly to the drawing, l denotes the tool as a whole including a cutter head 2, having a depending cylindrical body portion 3 adapted to be received within the cylinder bore 4 of an internal combustion engine, not shown. A centrally disposed upstanding projection 5 formed on the cutter head is provided with a threaded bore 6 communicating with an axially alined larger bore 1, extending to and through the body 3, for the reception of an expansion plug 8, herein described.

Cutter blades 9, preferably three in number, are slidably mounted in open ended radial slots 10 formed in the cutter head body portion 3 and extending from the bore 4 to and through the outer periphery of the said body 3. A flat plate H, secured to the flat bottom I2 of the cutter head by screws l3, holds the blades 9 within the slots Ill.

The tool as awhole is supported by a plurality of supporting arms or plates 14 mounted on the blades, one for each blade. These supporting members are preferably of substantially rectangular shape and are flat to conform with a flat upper surface l5 formed on the blade. Each supporting arm has a beveled face [6 formed on its inner end, which beveled face conforms with and is in the same plane with a beveled inner face ll of the blade. The supporting arms M are freely pivotally mounted on the upper surfaces I5 of the blades by means of upstanding members 18, such as lugs and pins, or the like. These pins or lugs are suitably positioned intermediate the Width of the blade and near the beveled inner end I! thereof. A small opening or bore I9 provided in the supporting arms intermediate the,

width of the arm is adapted to receive the upstanding pins 18 therein, whereby the supporting arms are pivotally and removably mounted on the blades. The arms are of such lengths that they are adapted to extend a suitable distance beyond the end faces 26 of the blades, as at 2|, which extended portions 2| are adapted to seat upon the cylinder block 22 and support 'the tool and blades in place. Expansion of the blade is effected by means of the beveled rotary expansion plug 8, the threaded stem 24 of which is mounted in the bore 6.

When the stem 24 of plug 8 is rotated in an appropriate direction, by a standard wrench or other suitable tool, not shown, the beveled face 25 of the body portion 26 of the plug will be moved downwardly against the beveled inner faces N5 of the supporting arms l4 and correspondingly beveled inner faces I! of the blades 9, thus forcing the blades outwardly into contact with the wall of cylinder bore 4. The tool as a whole is then turned approximately one revolution to the right or in a clockwise direction, by means ,of a suitable tool, not shown, applied to the squared end 21 of the tool shank 28, and this operation is repeated as often as necessary to remove the ridge 29, it being understood that the cutter blades will be slightly advanced or expanded after each revolution of the expander head, by rotating stem 24. If desirable rotation of the tool and feeding of the cutter blades can be simultaneously effected by the employment of two wrenches for turning the cutter head and expansion plug respectively. The cooperating beveled faces 25, I6 and l! of the expansion plug, I

supporting arms and cutter blades are preferably formed of an angle of approximately forty-five degrees to the axis of the cutter head, but any angularity may be employed provided the angle is the same on each face. It will be noted that the supporting arms i4 float freely on the top of the blades, due to the pivotal mounting, previously described, thus permitting the blades to accurately remove ridges from, or otherwise true the walls of the cylinder.

The outer or cutting end of each blade 9, which conforms in shape and structure with the cutter blade disclosed in my co-pending application Serial No. 727,827, is formed'with a pilot face 30, having front and rear edges 3| and 32. This face 30 is ground on a radius slightly less than the smallest radius of the work to be cut, so that a bearing will be had in the center of the face 30 directly under the cutting edge 33. An upper 'corner of the cutting end of the blade isv cut out, 7

as'at 34, to form a chip clearance, the forward edge 35 of which constitutes the sharp cutting edge previously referred to. It will'thus be seen that, by reason of the radius of the cutter face 30 being less than the smallest diameter of the work to be cut, the bearing on the pilot is always the centerof the pilot face 30. The cutting edge also being in the center allows this edge to remove the unworn ridge, and the pilot stops the 7 cutting immediately when it comes into contact with the worn part of the wall, thus preventing objectionable over cutting "or under cutting with consequent damage to the wall of the cylinder.

Heretofore considerable trouble has been lex-' perienced due to the fact that the arms or earswhich support the tool on the cylinder block, being cast on the body of the tool, frequently extend suficiently far over the top of the block ing the arms or supports for movement with the blades, this objection is overcome.

Having thus described my invention: What I claim is:

A tool of the character described comprising a slottedcutter head, cutter blades having vflat upper surfaces thereon, mounted in said slots, an upstanding pin member on said'flat surface adjacent the'inner end of each, of said blades, substantially rectangular supporting members in said slots and removably mounted on said upstanding pin member, said supporting members adapted to extend beyond the ends of saidrblades for supporting the tool upon a cylinder block; 7

LAWRENCE o. BEARD. 

